Looper and carrier therefor



Feb. 7 1956 B. N. PIERCE LOOPER AND CARRIER THEREFOR Filed- Jane 23. 1952 [72 v earl/Z502": fleriz rdZVT i 06 fluaflzd His-Attorneys United States Patent LOOPER AND CARRIER THEREFOR Bernard N. Pierce, West Hartford, Conn., assignor to The Merrow Machine Company, Hartford, Coma, a corporation of Connecticut Application June 23, 1952, Serial No. 295,036

15 Claims. (Cl. 112-162) looper carriers are lubricated and from such lubricated surfaces, stray oil flows onto the arm of the looper carrier. Vibration and centrifugal force move this stray oil along the arm of the looper carrier toward the end of the looper carrier. The transversely disposed surface at the end of the looper carrier causes most of this stray oil to be diverted laterally in a direction where it will do no harm. However, variations in the diameters of the looper shank and its socket in the looper carrier arm permit seepage of oil into the space between the socket wall and the shank. While seepage of oil in this manner is minute in quantity, vibration impels it in a jet or spray directly upon the work.

A major object of this invention is to prevent objectionable discharge of oil from the looper carrier socket into contact with the work. Another object of the invention is to provide a looper carrier mounting which accurately positions the looper both axially and angularly with respect to the looper carrier.

In the attainment of these objects, one feature of the invention resides in thearrangement of an annular shoulder on the shank of the looper of a diameter sufficiently greater than that of the shank as to present a transverse shoulder for engaging a seat at the rim of the socket in the arm of the looper carrier. To draw the shoulder on the shank into engagement with this seat, a set screw in the looper carrier intersects the socket and is offset laterally relative to the axis of the socket, so tightening of the screw shifts the shank axially of the socket and causes engagement of the shoulder with the seat surrounding the end of the socket. A counterbore in the end of the socket permits slight transverse movement of the shank to assure tight seating of the shoulder with the rim. The shoulder and its cooperating seat on the looper carrier are tapered to effect accurate alignment of the looper with its carrier.

These and other objects, advantages and features of the invention will become apparent from the following description taken in conjunction with the accompanying drawings wherein:

Fig. 1 is an end view of an overseaming machine showing looper carriers and loopers embodying the invention in its preferred form, certain elements of the machine being omitted for purposes of clarity;

Fig. 2 is a front view, partly in section, of the machine 2,733,675 Patented Feb. 7, 1956 shown in Fig. 1 and illustrating other parts relating to the looper carriers;

Fig. 3 is an enlarged detail view of the lower looper carrier shown in Fig. 2 with some parts broken away and others shown in section to illustrate the invention; and

Fig. 4 is a fragmentary cross-sectional view taken on the line 44 of Fig. 3.

In the drawings, the invention is shown embodied in a well-known Merrow overseaming machine. For a detailed illustration and description of this type of machine reference may be had to the aforementioned Patent No. 1,983,631.

As is characteristic of the Merrow overseaming machine, there is journaled in machine frame 11 a lower or main shaft 12 and an upper shaft 13 which are driven in unison to respectively rotate cam cylinders 14 and 15. Secured to the front of the machine frame 11, as by screws (not shown) is a frame cap 16 carrying an upper looper carrier 17 manipulated by cam rollers 18 and 19 riding in cam grooves 21 and 22 in the lower and upper cams 14 and 15. .Also carried by the frame cap 16 is a lower looper carrier 23 having a cam roller 24 for manipulation by cam groove 25 in the lower cam 14. Pivotally supported by a stud 26 at one end of machine frame 11 is a needle carrier 27 carrying a curved needle 28 manipulated by a link 29 connected between the carrier and a wrist pin 31 extending from an enlarged head 32 on the end of upper shaft 13.

As the shafts are turned, needle 28 is oscillated about the axis of stud 26; the cam cylinders revolve to oscillate lower looper 34 in a path extending across the path of the needle 28; and the upper looper 33 is reciprocated in a path crossing the paths of the lower looper 34 and the needle. Thus, the lower looper cooperates with the needle and the upper looper, and the upper looper in turn cooperates with the lower looper and the needle to form overedge stitches in a manner described in the aforementioned patent.

As the features of the present invention embodied in the upper looper and the upper carrier correspond to the same features incorporated in the lower looper and the lower carrier, a description of the lower looper carrier assembly will sufiice to explain the construction of the preferred embodiment of the invention.

As illustrated in Figs. 3 and 4, an arm 35 extending from the body of lower looper carrier 23 has a bore 36 forming a socket for receiving shank 37 on the looper 34. Near the outer end of arm 35, bore 36 is provided with a relief forming counterbore 38. At the outer end of the arm, counterbore 38 has a countersink 39. At a predetermined distance from the outer end 41 of looper 34, shank 37 has an annular shoulder or bead 42, formed 'as by swedging. This shoulder or bead is tapered to engage the correspondingly tapered wall of countersink 39. While valve-like in form, shoulder 42 does not necessarily fit within seat countersink 39 with the accuracy required to form a liquid-tight seal. The bead or shoulder acts as a looper endwise locating stop, as a looper centering or aligning means, and also presents a laterally extended wall for deflection of oil spurted from the socket formed by bore 36.

To facilitate the proper seating of the shoulder 42 with the seat 39, the counterbore 38 permits slight lateral shifting of the shank of the looper. Thus, even slight variations in the machining or formation of the shank or its socket will be accommodated so the tapered shoulder will accurately engage the rim of the arm.

Near the base of arm 35, carrier 23 is formed with a threaded hole 43 arranged to intersect the inner end of socket 36 so'the shank 37 in the socket 36 will be engaged by flattened end 44 of a set screw 45 inserted in the hole 43. Hole 43 and set screw 45 have their axes offset transversely with respect to the longitudinal axis of the socket 36 so the shank 37 will be engaged by that portionof the flat end 44 of screw 45 which is at one side of the axis of the screw. Hence, rotation of the screw 45 will move the end of the screw into engagement with the shank 37 and then by friction "cause axial shifting of the shank 37 inwardly to draw the shoulder 42 into engagement with seat 39 at the rim of the bore, thereby eflecting a snug'fit between the bead element and its seat.

Shank 37, at its inner end, may be'formed with a flat surface 46 to be engaged by the flat end 44 of the screw. This provides a greater surface contact between the screw and the shank so the axial shifting of the shank is effected with more positive action. In addition, this flattened surface 46 providesa plane to be engaged by the flat end of the screw and orients the shank 37 and the looper angularly about its own axis. With this arrangement, the engagement of the shoulder 42 with the end of the arm of the carrier positively positions the free end 41 of looper 34 a predetermined distance from the end of the arm and also angularly positions the looper in a predetermined position about the axis of the socket of the looper carrier.

To assemble looper 34 in its carrier 23, looper shank 37 is inserted in bore 36 until the tapered wall of the shoulder or bead 42 engages the correspondingly tapered wall of countersunk seat 39. As the shank is inserted in the socket, it is positioned so the fiat surface 46 is generally parallel to the flat surface 44 on the end of the screw 45. Then, screw 45'is advanced in its threaded hole to engage and laterally clamp the looper shank 37 within the socket 36. As the screw engages the shank, the shank is shifted longitudinally into the socket thereby drawing the tapered shoulder 42 into firm engagement with the i seat 3 9 at the rim of the bore to effect alignment of these parts.

As previously explained, the relief forming counterbore 38 of bore 36 permits concentric engagement between shoulder 42 and the seat or countersink 39 by allowing lateral shifting of the shank 37 within the counterbore 38; When the screw has been tightened so its fiat end is flush with the flat surface of the shank and the shoulder is snugly drawn against the seat at the end of the carrier arm, the looper is accurately positioned both longitudinally and angularly of its own axis. Any oil leaving the socket is transversely deflected by the shoulder way from the work.

As changes in construction and different embodiments could be made without departing from the invention, it is from said seat permitting lateral movement of the shank of the looper during engagement of the shoulder with said rim, said shank having a smaller diameter than said enlarged portion of said bore, and a screw threaded in said arm and intersecting said socket with its axis laterally offset relative to the axis of said bore so that a greater area of said looper is engageable with said screw on one side of the axis of said screw than on the other side of the axis of said screw whereby tightening of the screw against the shank of a looper in the socket draws the shoulder on the looper into engagement with said rim.

3. For use in a sewing machine, a looper having a cylindrical shank formed with a flat surface near one end to be engaged by a screw in the looper carrier for retaining said looper in a socket in said carrier, and an annular tapered shoulder on said shank between said surface and the outer free end of the looper for engaging a countersunk rim surrounding the end of the shank receivin g socket in the looper carrier.

4. In a sewing machine, the combination of a looper carrier having a bore therein forming a socket, said bore having an inwardly tapered rim, a looper having a shank for insertion in said socket, an annular tapered shoulder on said shank for engaging said rim of said bore, the diameter of said shoulder being greater than the diameter of said bore, and means on said carrier for clamping the shank of the looper in said socket.

. In a sewing machine, the combination of a looper carrier having a bore forming a socket, said bore having Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. In a sewing machine, a looper carrier comprising a body, an arm extending from said body provided with a. bore forming a socket for receiving the shank of a looper, said bore having a countersunk rim for engaging a tapered annular shoulder on the shank of the looper, and a screw threaded in said arm and intersecting said socketwith its axis oifset laterally relative to the axis of said bore so that a greater area of said looper is en- 7 gageable with said screw on one side of the axis of said an inwardly tapered rim, a looper having a shank for insertion in said socket, an annular tapered shoulder on said shank for engaging said rim of said bore, and means on said carrier for clamping the shank of the looper in said socket and simultaneously drawing the shank inwardly of said bore to seat said shoulder on said rim.

6. In a sewing machine, the combination of a looper carrier, an arm on said looper carrier having a longitudinally extending bore forming a socket and a counterbore extending inwardly from the end of said arm, the outer end of said counterbore having a countersunk rim, a looper having a shank for insertion in said socket, the diameter of said shank being less than the diameter of said counterbore, said counterbore permitting lateral movement of said shank within the end of said arm, an annular tapered shoulder on said shank for engaging the rim of said counterbore, the diameter of said shoulder being greater than the diameter of said counterbore, and means on said carrier 'for retaining the shank of the looper in'said socket.

7. In a sewing machine, the combination of a looper carrier having an arm provided with a bore forming a socket and a counterbore extending inwardly from the end of said arm, the outer end of said counterbore having a countersunk rim, a looper having a shank for insertion in said bore, the diameter of said shank being less than the diameter of said counterbore, said counterbore permitting lateral movement of said shank in the end of said arm, an annular tapered shoulder on said shank for engaging the rim of said counterbore, the diameter of said shoulder being greater than the diameter of said counterbore, and means on said carrier for clamping said shank in said socket and simultaneously shifting said shank axially inwardly to draw said shoulder against said rim.

8. in a sewing machine, the combination of a looper carrier having a bore forming a socket and a threaded hole transversely intersecting said socket, said bore having a countersunk rim, a looper having a shank for insertion in said socket, an annular tapered shoulder formed on said shank for engaging said rim of said bore, and a screw in said threaded hole for clamping the shank of the looper laterally in said socket and simultaneously drawing the shoulder of the looper against the rim of said bore,-the axis of said screw being laterally offset from the axis of the shank of said looper so that a greater area of said shank is engageable with said screw on one side of the axis of said screw than on the other side of the axis of said screw.

9. In a sewing machine, the combination of a looper carrier, an arm on said carrier having a longitudinal bore forming a socket and a counterbore extending inwardly from the end of said arm, said counterbore having a countersunk rim at the outer end thereof, said carrier being formed with a threaded hole transversely intersecting said socket and laterally ofiset relative to the axis of said bore, a looper having a shank for insertion in said socket, the diameter of said shank being less than the diameter of said counterbore, said counterbore permitting lateral movement of said shank in the end of said arm, an annular tapered shoulder on said shank for engagement with the rim of said counterbore, the diameter of said shoulder being greater than the diameter of said counterbore, and a screw in said threaded hole operable to clamp the shank of the looper laterally in said socket and shift said shank axially to draw said shoulder against said rim of said counterbore.

10. In a sewing machine, the combination defined in claim 8 wherein said shank has a flattened side for engagement by said screw.

11. In a sewing machine, the combination defined in claim 9 wherein said shank has a flattened side for engagement by said screw.

12. In a sewing machine, the combination of a looper carrier, an arm extending from said carrier, said arm having a longitudinally extending bore forming a socket and a countersunk counterbore extending inwardly from the end of said arm, a looper having a shank for insertion in said socket, an annular shoulder on said shank tapered to snugly fit the wall of the countersunk rim of said counterbore, the diameter of said shoulder being greater than the diameter of said counterbore, and means for retaining said shank in said socket.

13. In a sewing machine, the combinaton of a looper carrier having a bore forming a socket, a looper having a shank for insertion in said bore, the end of said bore being countersunk to provide a seat, a tapered annular shoulder on said shank for engaging the wall of said seat, the diameter of said shoulder being. greater than the diameter of said bore, and means for retaining said shank in said socket.

14. In a sewing machine, the combination of a looper carrier having an arm with a bore extending longitudinally thereof forming a socket, said bore having a countersunk rim forming a seat, a looper having a shank for insertion in said socket, said carrier being formed with a threaded hole transversely intersecting said socket and laterally offset relative to the axis of said bore, a tapered annular shoulder on said shank for engaging the counter sunk rim of said bore, the diameter of said shoulder being greater than the diameter of said bore, and a screw disposed in said threaded hole for clamping the shank of the looper laterally in said socket and simultaneously shifting said shank axially to draw said shoulder against said rim.

15. In a sewing machine, the combination defined in claim 14 wherein said shank is formed with a fiat side for engagement by said screw.

References Cited in the file of this patent UNITED STATES PATENTS 400,432 Boland Apr. 2, 1889 1,983,631 Merrow Dec. 11, 1934 2,189,041 Kierner Feb. 6, 1940 2,549,839 Mollis Apr. 24, 1951 

